US4946849A - Method for the treatment of malaria - Google Patents
Method for the treatment of malaria Download PDFInfo
- Publication number
- US4946849A US4946849A US07/418,086 US41808689A US4946849A US 4946849 A US4946849 A US 4946849A US 41808689 A US41808689 A US 41808689A US 4946849 A US4946849 A US 4946849A
- Authority
- US
- United States
- Prior art keywords
- malaria
- dequalinium
- salt
- animal
- administration
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 201000004792 malaria Diseases 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims description 18
- PCSWXVJAIHCTMO-UHFFFAOYSA-P dequalinium Chemical class C1=CC=C2[N+](CCCCCCCCCC[N+]3=C4C=CC=CC4=C(N)C=C3C)=C(C)C=C(N)C2=C1 PCSWXVJAIHCTMO-UHFFFAOYSA-P 0.000 claims abstract description 38
- 150000003839 salts Chemical class 0.000 claims abstract description 8
- 244000045947 parasite Species 0.000 claims description 33
- 241001465754 Metazoa Species 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 6
- 238000007920 subcutaneous administration Methods 0.000 claims description 4
- 230000037396 body weight Effects 0.000 claims description 3
- XMBWDFGMSWQBCA-UHFFFAOYSA-N hydrogen iodide Chemical compound I XMBWDFGMSWQBCA-UHFFFAOYSA-N 0.000 claims description 3
- 238000007912 intraperitoneal administration Methods 0.000 claims description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 claims description 2
- CPELXLSAUQHCOX-UHFFFAOYSA-M Bromide Chemical compound [Br-] CPELXLSAUQHCOX-UHFFFAOYSA-M 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- 239000007864 aqueous solution Substances 0.000 claims description 2
- 238000001990 intravenous administration Methods 0.000 claims 2
- BICAGYDGRXJYGD-UHFFFAOYSA-N hydrobromide;hydrochloride Chemical compound Cl.Br BICAGYDGRXJYGD-UHFFFAOYSA-N 0.000 claims 1
- 150000003873 salicylate salts Chemical class 0.000 claims 1
- 241000223960 Plasmodium falciparum Species 0.000 abstract description 16
- WHTVZRBIWZFKQO-AWEZNQCLSA-N (S)-chloroquine Chemical compound ClC1=CC=C2C(N[C@@H](C)CCCN(CC)CC)=CC=NC2=C1 WHTVZRBIWZFKQO-AWEZNQCLSA-N 0.000 abstract description 13
- 229960003677 chloroquine Drugs 0.000 abstract description 13
- WHTVZRBIWZFKQO-UHFFFAOYSA-N chloroquine Natural products ClC1=CC=C2C(NC(C)CCCN(CC)CC)=CC=NC2=C1 WHTVZRBIWZFKQO-UHFFFAOYSA-N 0.000 abstract description 13
- 238000002560 therapeutic procedure Methods 0.000 abstract description 3
- 101001131829 Homo sapiens P protein Proteins 0.000 abstract description 2
- 102000047119 human OCA2 Human genes 0.000 abstract description 2
- 230000002141 anti-parasite Effects 0.000 abstract 1
- 229960000840 dequalinium Drugs 0.000 description 12
- 201000010099 disease Diseases 0.000 description 9
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 9
- LOUPRKONTZGTKE-WZBLMQSHSA-N Quinine Chemical compound C([C@H]([C@H](C1)C=C)C2)C[N@@]1[C@@H]2[C@H](O)C1=CC=NC2=CC=C(OC)C=C21 LOUPRKONTZGTKE-WZBLMQSHSA-N 0.000 description 8
- 150000001875 compounds Chemical class 0.000 description 8
- 210000003936 merozoite Anatomy 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 210000003743 erythrocyte Anatomy 0.000 description 7
- 241000256186 Anopheles <genus> Species 0.000 description 6
- 230000012010 growth Effects 0.000 description 6
- 239000000463 material Substances 0.000 description 6
- 230000000699 topical effect Effects 0.000 description 6
- 102000000584 Calmodulin Human genes 0.000 description 5
- 108010041952 Calmodulin Proteins 0.000 description 5
- LTNZEXKYNRNOGT-UHFFFAOYSA-N dequalinium chloride Chemical compound [Cl-].[Cl-].C1=CC=C2[N+](CCCCCCCCCC[N+]3=C4C=CC=CC4=C(N)C=C3C)=C(C)C=C(N)C2=C1 LTNZEXKYNRNOGT-UHFFFAOYSA-N 0.000 description 5
- 235000001258 Cinchona calisaya Nutrition 0.000 description 4
- LOUPRKONTZGTKE-UHFFFAOYSA-N cinchonine Natural products C1C(C(C2)C=C)CCN2C1C(O)C1=CC=NC2=CC=C(OC)C=C21 LOUPRKONTZGTKE-UHFFFAOYSA-N 0.000 description 4
- 229960001378 dequalinium chloride Drugs 0.000 description 4
- 210000005229 liver cell Anatomy 0.000 description 4
- 229960000948 quinine Drugs 0.000 description 4
- 108091006112 ATPases Proteins 0.000 description 3
- 102000057290 Adenosine Triphosphatases Human genes 0.000 description 3
- 102000003923 Protein Kinase C Human genes 0.000 description 3
- 108090000315 Protein Kinase C Proteins 0.000 description 3
- 241000700159 Rattus Species 0.000 description 3
- 229940034982 antineoplastic agent Drugs 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 230000036039 immunity Effects 0.000 description 3
- 230000005764 inhibitory process Effects 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 230000010534 mechanism of action Effects 0.000 description 3
- 210000003046 sporozoite Anatomy 0.000 description 3
- 206010003399 Arthropod bite Diseases 0.000 description 2
- 206010063094 Cerebral malaria Diseases 0.000 description 2
- 241000282412 Homo Species 0.000 description 2
- 206010028980 Neoplasm Diseases 0.000 description 2
- 208000030852 Parasitic disease Diseases 0.000 description 2
- 241000224016 Plasmodium Species 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 239000005557 antagonist Substances 0.000 description 2
- 230000000844 anti-bacterial effect Effects 0.000 description 2
- 230000001093 anti-cancer Effects 0.000 description 2
- 239000002246 antineoplastic agent Substances 0.000 description 2
- 238000003556 assay Methods 0.000 description 2
- 210000004369 blood Anatomy 0.000 description 2
- 239000008280 blood Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 230000034994 death Effects 0.000 description 2
- 231100000517 death Toxicity 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 239000003814 drug Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 210000003470 mitochondria Anatomy 0.000 description 2
- 230000002438 mitochondrial effect Effects 0.000 description 2
- 239000002324 mouth wash Substances 0.000 description 2
- 210000000287 oocyte Anatomy 0.000 description 2
- 241000894007 species Species 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 210000001519 tissue Anatomy 0.000 description 2
- 210000003934 vacuole Anatomy 0.000 description 2
- 208000030507 AIDS Diseases 0.000 description 1
- 241000283690 Bos taurus Species 0.000 description 1
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- 208000035473 Communicable disease Diseases 0.000 description 1
- 241000255925 Diptera Species 0.000 description 1
- 102000004190 Enzymes Human genes 0.000 description 1
- 108090000790 Enzymes Proteins 0.000 description 1
- 208000002476 Falciparum Malaria Diseases 0.000 description 1
- 206010019233 Headaches Diseases 0.000 description 1
- 208000008454 Hyperhidrosis Diseases 0.000 description 1
- 241000699670 Mus sp. Species 0.000 description 1
- 102000004861 Phosphoric Diester Hydrolases Human genes 0.000 description 1
- 108090001050 Phosphoric Diester Hydrolases Proteins 0.000 description 1
- 206010035500 Plasmodium falciparum infection Diseases 0.000 description 1
- 201000011336 Plasmodium falciparum malaria Diseases 0.000 description 1
- 241000223821 Plasmodium malariae Species 0.000 description 1
- 206010035501 Plasmodium malariae infection Diseases 0.000 description 1
- 241001505293 Plasmodium ovale Species 0.000 description 1
- 206010035502 Plasmodium ovale infection Diseases 0.000 description 1
- 241000223810 Plasmodium vivax Species 0.000 description 1
- 206010037660 Pyrexia Diseases 0.000 description 1
- 101100386054 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) CYS3 gene Proteins 0.000 description 1
- 241000509427 Sarcoptes scabiei Species 0.000 description 1
- 206010047700 Vomiting Diseases 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 159000000021 acetate salts Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 230000000843 anti-fungal effect Effects 0.000 description 1
- 230000002529 anti-mitochondrial effect Effects 0.000 description 1
- 230000000118 anti-neoplastic effect Effects 0.000 description 1
- 230000000840 anti-viral effect Effects 0.000 description 1
- 239000004599 antimicrobial Substances 0.000 description 1
- 239000003096 antiparasitic agent Substances 0.000 description 1
- 229940125687 antiparasitic agent Drugs 0.000 description 1
- 239000003443 antiviral agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 201000011510 cancer Diseases 0.000 description 1
- 150000001767 cationic compounds Chemical class 0.000 description 1
- 230000010261 cell growth Effects 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 150000003841 chloride salts Chemical class 0.000 description 1
- 208000029742 colonic neoplasm Diseases 0.000 description 1
- CJZYFXLJFNDALI-UHFFFAOYSA-N cyclohexa-1,3-dien-1-amine Chemical compound NC1=CC=CCC1 CJZYFXLJFNDALI-UHFFFAOYSA-N 0.000 description 1
- 238000004163 cytometry Methods 0.000 description 1
- QAYICIQNSGETAS-UHFFFAOYSA-N dazomet Chemical compound CN1CSC(=S)N(C)C1 QAYICIQNSGETAS-UHFFFAOYSA-N 0.000 description 1
- 230000001079 digestive effect Effects 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000009510 drug design Methods 0.000 description 1
- 238000002651 drug therapy Methods 0.000 description 1
- 239000003885 eye ointment Substances 0.000 description 1
- 206010016256 fatigue Diseases 0.000 description 1
- 238000000684 flow cytometry Methods 0.000 description 1
- 210000000973 gametocyte Anatomy 0.000 description 1
- 230000009036 growth inhibition Effects 0.000 description 1
- 231100000869 headache Toxicity 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 210000000987 immune system Anatomy 0.000 description 1
- 238000000338 in vitro Methods 0.000 description 1
- 230000002779 inactivation Effects 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 208000015181 infectious disease Diseases 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 210000004185 liver Anatomy 0.000 description 1
- 230000004807 localization Effects 0.000 description 1
- 238000002483 medication Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000004719 natural immunity Effects 0.000 description 1
- 230000001613 neoplastic effect Effects 0.000 description 1
- 239000002547 new drug Substances 0.000 description 1
- 235000003715 nutritional status Nutrition 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000036281 parasite infection Effects 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 208000018299 prostration Diseases 0.000 description 1
- 102000004169 proteins and genes Human genes 0.000 description 1
- 108090000623 proteins and genes Proteins 0.000 description 1
- 229940126409 proton pump inhibitor Drugs 0.000 description 1
- 239000000612 proton pump inhibitor Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- UKOBAUFLOGFCMV-UHFFFAOYSA-N quinacrine mustard Chemical compound C1=C(Cl)C=CC2=C(NC(C)CCCN(CCCl)CCCl)C3=CC(OC)=CC=C3N=C21 UKOBAUFLOGFCMV-UHFFFAOYSA-N 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- YGSDEFSMJLZEOE-UHFFFAOYSA-M salicylate Chemical compound OC1=CC=CC=C1C([O-])=O YGSDEFSMJLZEOE-UHFFFAOYSA-M 0.000 description 1
- 229960001860 salicylate Drugs 0.000 description 1
- 210000003079 salivary gland Anatomy 0.000 description 1
- 239000012266 salt solution Substances 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 230000001568 sexual effect Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 101150035983 str1 gene Proteins 0.000 description 1
- 238000005556 structure-activity relationship Methods 0.000 description 1
- 230000035900 sweating Effects 0.000 description 1
- 238000007910 systemic administration Methods 0.000 description 1
- 229940124597 therapeutic agent Drugs 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000004614 tumor growth Effects 0.000 description 1
- 239000000522 vaginal cream Substances 0.000 description 1
- 230000008673 vomiting Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K31/00—Medicinal preparations containing organic active ingredients
- A61K31/33—Heterocyclic compounds
- A61K31/395—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
- A61K31/435—Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having six-membered rings with one nitrogen as the only ring hetero atom
- A61K31/47—Quinolines; Isoquinolines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
- Y02A50/30—Against vector-borne diseases, e.g. mosquito-borne, fly-borne, tick-borne or waterborne diseases whose impact is exacerbated by climate change
Definitions
- the present invention generally relates to a disease treatment method, and more specifically to a method for treating malaria.
- Malaria is a dangerous disease caused by a protozoic parasite which invades a host's liver cells and erythrocytes. It is one of the most wide-spread infectious diseases.
- the World Health Organization estimates that 200,000,000 people are infected with the malaria parasite annually. These people mainly reside in the tropics.
- One million cases of malaria were reported in the U.S. in 1940.
- effective measures were introduced which virtually eliminated the disease, which is transmitted by the female Anopheles mosquito.
- the Anopheles mosquito is still present in many of the Southern and Western parts of the U.S.
- the life cycle of a Plasmodium parasite involves the interrelationship between an Anopheles mosquito vector and a mammalian host.
- an uninfected female Anopheles mosquito bites and ingests blood from a host harboring the sexual forms of the Plasmodium parasite
- the parasitic life cycle begins.
- the male and female gametocytes fuse and travel after several stages of development to the salivary glands of the mosquito.
- the parasite at this stage is called a "sporozoite.” If the infected mosquito bites a new host, the sporozoites are injected into the host's blood. Thereafter, they travel to the liver within 30 minutes, where they enter a liver cell.
- one sporozoite multiplies and forms about 10,000-20,000 merozoites. These merozoites are released from the liver cells in 10-12 days. Each of the released merozoites immediately invades an erythrocyte. In 48 hours, each merozoite forms another 10-12 merozoites which are in turn released from the erythrocyte only to invade another 10-12 erythrocytes.
- the clinical manifestations of the disease include fever, headaches, sweating, vomiting, and prostration. These manifestations occur simultaneously with merozoite release from the erythrocytes.
- the erythrocyte reinvasion occurs until the host dies, or until the host's immune system is able to control and suppress merozoite activity.
- the merozoites previously asexual
- the technical and scientific basis for this transformation is an active area of current medical research. If a female Anopheles then bites a new host at the time of gametocyte formation, the life cycle of the parasite is completed.
- chloroquine and quinine have been used over the past thirty years.
- chloroquine-resistant malaria strains of P. falciparum the malaria parasite responsible for 1.6 million deaths annually
- quinine-resistant strains of P. falciparum the malaria parasite responsible for 1.6 million deaths annually
- many corporations and governments have spent billions of dollars in attempts to develop new drug therapies for the disease, with an inconsequential degree of success.
- the present invention represents a new and effective therapeutic method for treating malaria. It offers a superior degree of efficacy, safety, and utility compared with currentlyused compounds.
- the present invention involves a safe and effective method for malarial infections which involves the systemic administration of a selected salt of dequalinium.
- Dequalinium salts have a high degree of effectiveness against chloroquine resistant/sensitive strains of human P. falciparum at minimal (nanogram) quantities. Accordingly, the dequalinium compounds described herein represent an advance in the art of malaria control.
- FIG. 1 is a graphical representation of test data obtained when chloroquine-resistant strains of P. falciparum were treated with a dequalinium salt at nanogram quantities.
- the present invention involves a highly effective therapeutic method for treating malaria described in detail herein.
- malaria is controlled by the administration of a selected dequalinium salt.
- Dequalinium and its salts were originally synthesized and patented in England. Specifically, these materials are described in British Patent No. 745,956 issued in 1956. They are also discussed in the Merck Index, 9th ed., 1976 (compounds 2873-2874 on page 381).
- Dequalinium and its salts have been used extensively as topical anti-bacterial and anti-fungal compounds in skin medications, ophthalmic ointments, vaginal creams, and mouthwashes. They have also been used as anti-neoplastic agents, and in oral solutions for oral/buccal diseases.
- Romanian Patent No. 76918 discloses the topical use of dequalinium compounds to control Sarcoptes scabiei (a mite).
- dequalinium was approved for topical use as a wound dressing by the FDA in 1976.
- dequalinium compositions for topical use including mouthwashes have a dequalinium concentration of 0.001% (10 micrograms/ml). This concentration level is many thousand times greater than the dequalinium concentration levels which are capable of inhibiting P. falciparum growth, as described herein below.
- Dequalinium materials are chemically characterized as lipophilic cationic compounds.
- the basic structure of a dequalinium salt is as follows: ##STR1## This material is known as 1,1'-(1,10-Decanediyl)bis-[4-amino-2-methylquinolinium] salt or as a 1,1'-decamethylenebis[4aminoquinaldinium] salt.
- sterilization of in vitro cultures of P. falciparum occurs at concentration levels of 1.0 microgram/ml or less, as described in greater detail below.
- dequalinium compounds are highly effective against malaria parasites in humans and other warm-blooded animals.
- a selected dequalinium salt e.g. dequalinium chloride
- an aqueous solution e.g. water
- the total dosage of compound administered would be about 7 mg of dequalinium salt per kg of body weight over a 3-5 day period.
- the total compound dosage may be experimentally varied depending upon a variety of factors, including the age, size (weight), and nutritional status of the subject, as well as the exact concentration level of the compound and extent of parasitic infection.
- dequalinium compounds there are numerous theoretical mechanisms of action which may explain the effectiveness of dequalinium compounds in controlling malaria.
- One mechanism involves the possible accumulation of dequalinium compounds in mitochondria. This mechanism is discussed in Weiss, et al., Proc. Nat. Acad. Sci., 84:5444-5448 (1987) with respect to the use of dequalinium as a topical therapeutic agent for neoplastic tissues. More specifically, dequalinium compounds may bind to calmodulin in parasite mitochondria.
- Calmodulin is an essential protein for the activation of phosphodiesterase which is necessary for cell growth as discussed in Bodden et al., "Selective Antimitochondrial Agents Inhibit Calmodulin" Bioohv. Res.
- a second suggested mechanism of action involves the ability of dequalinium compounds to inhibit the ATPases of cellular tissues, as discussed in Bullough, D. A. et al., "Localization of Sites Modified During Inactivation of the Bovine Heart Mitochondrial F 1 -ATPase By Quinacrine Mustard Using [ 3 H]Aniline as a Probe” J. Biol. Chem.264:9155-9163 (1989).
- ATPases are present on the membranes of the parasitophorous vacuoles of P. falciparum parasites, and these enzymes are inhibited by proton pump inhibitors as discussed in Choy, I. and Mego, J. L., "Purification of Plasmodium Falciparum Digestive Vacuoles and Partial Characterization of the Vacuolar Membrane ATPase” Mol. Biochem. Parasit. 31:71-78 (1988).
- an additional mechanism of action may involve the ability of dequalinium compounds to inhibit protein kinase C as discussed in Rotenberg, S. A. et al., "Inhibition of protein kinase C by the anticarcinoma agent dequalinium. Structure-activity relationships.” Proc. Annu. Meet. Am. Assoc. Cancer Res., 30:a25 (1989).
- Rotenberg, S. A. et al. "Inhibition of protein kinase C by the anticarcinoma agent dequalinium. Structure-activity relationships.” Proc. Annu. Meet. Am. Assoc. Cancer Res., 30:a25 (1989).
- dequalinium compounds are surprisingly effective in controlling the propagation of malaria parasites. This characteristic has not been suggested or recognized in the relevant chemical literature, which is primarily directed to the use of dequalinium compounds as topical anti-bacterial, anti-viral or antineoplastic agents.
- the parasites were permitted to incubate in the test media for 72 hours. At 24 hour intervals, new media and test substances were added, and an aliquot of the incubation mixture was removed for microscopic examination, In addition, the parasites were examined by flow cytometry using the techniques discussed in Makler, M. T., et al., "Thiazone Orange: A New Dye for Plasmodium Species Analysis” Cytometry, 8:568-570 (1987).
- the entire experiment was terminated after three days.
- the data in FIG. 1 clearly illustrates the effectiveness of dequalinium salts against chloroquine-resistant parasites.
- the "Y” axis in FIG. 1 involves the percentage of erythrocytes in the test media which were infected with viable parasites.
- the "X” axis involves the concentration of dequalinium chloride used (in nanograms/ml.) At 0 nanograms/ml, parasite growth was extensive, with a % parasite infection of about 17 % after 72 hours. However, at a concentration level of 1.0 nanogram/ml and above, parasite growth was strongly inhibited, and after 72 hours, no viable parasites remained. Similar results were obtained with the chloroquine-sensitive strains of parasite.
Landscapes
- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Pharmacology & Pharmacy (AREA)
- Epidemiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Abstract
A safe and effective therapeutic method for treating malaria. To accomplish treatment , anti-parasite agents are administered which consist of dequalinium salts. The salts are highly effective against chloroquine resistant/sensitive strains of human P. falciparum at low concentration levels.
Description
The present invention generally relates to a disease treatment method, and more specifically to a method for treating malaria.
Malaria is a dangerous disease caused by a protozoic parasite which invades a host's liver cells and erythrocytes. It is one of the most wide-spread infectious diseases. The World Health Organization estimates that 200,000,000 people are infected with the malaria parasite annually. These people mainly reside in the tropics. One million cases of malaria were reported in the U.S. in 1940. At that time, effective measures were introduced which virtually eliminated the disease, which is transmitted by the female Anopheles mosquito. However, the Anopheles mosquito is still present in many of the Southern and Western parts of the U.S. During the early 1970's, there were several cases of malaria reported in Louisiana and California. These were attributed to returning veterans from the Viet Nam War who harbored the parasite.
As tropical regions of the world become more accessible through improved modes of transportation, travel into these areas is increasing. This has resulted in significantly more cases of malaria being reported in travelers returning from these areas. One percent (1%) of all people infected with the malaria parasite die from the disease (2,000,000 people per year). There are four species of Plasmodium which infect humans and cause malaria. These include P. falciparum. P. vivax, P. ovale, and P. malariae. P. falciparum is the most serious species. It is responsible for cerebral malaria which is associated with a 50% mortality rate.
The life cycle of a Plasmodium parasite involves the interrelationship between an Anopheles mosquito vector and a mammalian host. When an uninfected female Anopheles mosquito bites and ingests blood from a host harboring the sexual forms of the Plasmodium parasite, the parasitic life cycle begins. In the Anopheles, the male and female gametocytes fuse and travel after several stages of development to the salivary glands of the mosquito. The parasite at this stage is called a "sporozoite." If the infected mosquito bites a new host, the sporozoites are injected into the host's blood. Thereafter, they travel to the liver within 30 minutes, where they enter a liver cell. In the liver cell, one sporozoite multiplies and forms about 10,000-20,000 merozoites. These merozoites are released from the liver cells in 10-12 days. Each of the released merozoites immediately invades an erythrocyte. In 48 hours, each merozoite forms another 10-12 merozoites which are in turn released from the erythrocyte only to invade another 10-12 erythrocytes.
The clinical manifestations of the disease include fever, headaches, sweating, vomiting, and prostration. These manifestations occur simultaneously with merozoite release from the erythrocytes. The erythrocyte reinvasion occurs until the host dies, or until the host's immune system is able to control and suppress merozoite activity. At some point, the merozoites (previously asexual) differentiate into male and female gametocytes. The technical and scientific basis for this transformation is an active area of current medical research. If a female Anopheles then bites a new host at the time of gametocyte formation, the life cycle of the parasite is completed.
The most susceptible human hosts for the disease are infants and pregnant women having suppressed immunity. Recently, deaths have been reported in adult male AIDS patients caused by cerebral malaria. In addition, non-immune travelers into high-risk malaria areas are also susceptible to the disease, especially with respect to chloroquine and quinine resistant malaria.
There is a natural immunity to malaria which develops in persons living in high-risk malaria areas. This immunity appears to depend upon the continual presence of low parasite levels in the host's body. This conclusion is drawn from many studies which demonstrate that when persons living in high-risk malaria areas leave for a variety of reasons and travel to low risk areas, they substantially lose their immunity.
Many chemical agents have been developed to treat malaria. For example, chloroquine and quinine have been used over the past thirty years. However, chloroquine-resistant malaria strains of P. falciparum (the malaria parasite responsible for 1.6 million deaths annually) have spread from two to seventy countries throughout the world. In addition, there are twelve countries which have reported quinine-resistant strains of P. falciparum. As a result, many corporations and governments have spent billions of dollars in attempts to develop new drug therapies for the disease, with an inconsequential degree of success.
The present invention represents a new and effective therapeutic method for treating malaria. It offers a superior degree of efficacy, safety, and utility compared with currentlyused compounds.
It is an object of the present invention to provide a method for treating malaria having an improved degree of effectiveness.
It is another object of the invention to provide a method for treating malaria using a chemical compound characterized by a low degree of human toxicity.
It is a further object of the invention to provide a method for treating malaria which uses readily available, inexpensive materials.
It is a still further object of the invention to provide a method for treating malaria which uses a chemical compound that is effective at low concentration levels.
It is an even further object of the invention to provide a method for treating malaria which is highly effective against parasites having resistance to currently available antiparasitic agents, including chloroquine and quinine.
In accordance with the foregoing objects, the present invention involves a safe and effective method for malarial infections which involves the systemic administration of a selected salt of dequalinium. Dequalinium salts have a high degree of effectiveness against chloroquine resistant/sensitive strains of human P. falciparum at minimal (nanogram) quantities. Accordingly, the dequalinium compounds described herein represent an advance in the art of malaria control.
These and other objects, features, and advantages of the invention shall be described below in the following detailed description of a preferred embodiment, experimental examples, and drawing figures.
FIG. 1 is a graphical representation of test data obtained when chloroquine-resistant strains of P. falciparum were treated with a dequalinium salt at nanogram quantities.
The present invention involves a highly effective therapeutic method for treating malaria described in detail herein. In accordance with the invention, malaria is controlled by the administration of a selected dequalinium salt. Dequalinium and its salts were originally synthesized and patented in Britain. Specifically, these materials are described in British Patent No. 745,956 issued in 1956. They are also discussed in the Merck Index, 9th ed., 1976 (compounds 2873-2874 on page 381).
Dequalinium and its salts (chloride, salicylate, bromide, iodide, and acetate) have been used extensively as topical anti-bacterial and anti-fungal compounds in skin medications, ophthalmic ointments, vaginal creams, and mouthwashes. They have also been used as anti-neoplastic agents, and in oral solutions for oral/buccal diseases. For example, Romanian Patent No. 76918 discloses the topical use of dequalinium compounds to control Sarcoptes scabiei (a mite). In addition, dequalinium was approved for topical use as a wound dressing by the FDA in 1976.
Specific studies have been conducted in order to evaluate the anti-neoplastic characteristics of dequalinium materials. As discussed in Bleday, R. et al., "Inhibition of Rat Colon Tumor Isograft Growth With Dequalinium Chloride" Arch. Surg. 121:1272-1275 (1986) and Weiss, M. J., et al., "Dequalinium, A Tropical Antimicrobial Agent, Displays Anticarcinoma Activity Based On Selective Mitochondrial Accumulation" Proc. Nat. Acad. Sci., 84:5444-5448 (1987), tumor-bearing animal (rat) studies were conducted involving dequalinium chloride. The rats receiving a sublethal dose (1.0 mg/kg) by subcutaneous, intraperitoneal, or implant-osmotic pump administration all survived and demonstrated significant tumor growth inhibition.
Most dequalinium compositions for topical use including mouthwashes have a dequalinium concentration of 0.001% (10 micrograms/ml). This concentration level is many thousand times greater than the dequalinium concentration levels which are capable of inhibiting P. falciparum growth, as described herein below.
Dequalinium materials are chemically characterized as lipophilic cationic compounds. The basic structure of a dequalinium salt is as follows: ##STR1## This material is known as 1,1'-(1,10-Decanediyl)bis-[4-amino-2-methylquinolinium] salt or as a 1,1'-decamethylenebis[4aminoquinaldinium] salt. The chloride salt consists of C30 H40 Cl2 N4 (C=68.30%; H=7.64%; Cl=13.44%; and N=10.62%) with a molecular weight of 527.60. It has an LD50 s.c. in mice of 70 mg/kg. In addition, sterilization of in vitro cultures of P. falciparum occurs at concentration levels of 1.0 microgram/ml or less, as described in greater detail below.
The acetate salt consists of C34 H46 N4 O4 (C=71.05%; H=8.07%; N=9.75%; and 0=11.14%) with a molecular weight of 574.74.
In accordance with the invention, it has been discovered that dequalinium compounds are highly effective against malaria parasites in humans and other warm-blooded animals. To control malaria parasites in an animal subject, a selected dequalinium salt (e.g. dequalinium chloride) is administered in an aqueous solution (e.g. water) either orally, intravenously, intraperitoneally or subcutaneously at a preferred dequalinium salt concentration level of about 1.0 microgram/ml or less. In a preferred embodiment, the total dosage of compound administered would be about 7 mg of dequalinium salt per kg of body weight over a 3-5 day period. However, the total compound dosage may be experimentally varied depending upon a variety of factors, including the age, size (weight), and nutritional status of the subject, as well as the exact concentration level of the compound and extent of parasitic infection.
There are numerous theoretical mechanisms of action which may explain the effectiveness of dequalinium compounds in controlling malaria. One mechanism involves the possible accumulation of dequalinium compounds in mitochondria. This mechanism is discussed in Weiss, et al., Proc. Nat. Acad. Sci., 84:5444-5448 (1987) with respect to the use of dequalinium as a topical therapeutic agent for neoplastic tissues. More specifically, dequalinium compounds may bind to calmodulin in parasite mitochondria. Calmodulin is an essential protein for the activation of phosphodiesterase which is necessary for cell growth as discussed in Bodden et al., "Selective Antimitochondrial Agents Inhibit Calmodulin" Bioohv. Res. Comm., 35:574-582 (1986). It has also been shown in Scheibel, L. "Calcium and Calmodulin Antagonists Inhibit Human Malaria Parasites (Plasmodium Falciparum): Implications For Drug Design" Proc. Nat. Acad. Sci., 84:7310-7314 (1987) that calmodulin antagonists generally inhibit human malaria parasites.
A second suggested mechanism of action involves the ability of dequalinium compounds to inhibit the ATPases of cellular tissues, as discussed in Bullough, D. A. et al., "Localization of Sites Modified During Inactivation of the Bovine Heart Mitochondrial F1 -ATPase By Quinacrine Mustard Using [3 H]Aniline as a Probe" J. Biol. Chem.264:9155-9163 (1989). ATPases are present on the membranes of the parasitophorous vacuoles of P. falciparum parasites, and these enzymes are inhibited by proton pump inhibitors as discussed in Choy, I. and Mego, J. L., "Purification of Plasmodium Falciparum Digestive Vacuoles and Partial Characterization of the Vacuolar Membrane ATPase" Mol. Biochem. Parasit. 31:71-78 (1988).
Finally, an additional mechanism of action may involve the ability of dequalinium compounds to inhibit protein kinase C as discussed in Rotenberg, S. A. et al., "Inhibition of protein kinase C by the anticarcinoma agent dequalinium. Structure-activity relationships." Proc. Annu. Meet. Am. Assoc. Cancer Res., 30:a25 (1989). However, there is no currently available information as to the role protein kinase C plays in the growth/development of malaria parasites.
Regardless of its suggested mechanism of action, dequalinium compounds are surprisingly effective in controlling the propagation of malaria parasites. This characteristic has not been suggested or recognized in the relevant chemical literature, which is primarily directed to the use of dequalinium compounds as topical anti-bacterial, anti-viral or antineoplastic agents.
Numerous experiments were conducted regarding dequalinium compounds and their ability to control the growth of chloroquine-resistant and sensitive strains of P. falciparum malaria parasites. Specifically, two commonly-known strains of P. falciparum were obtained from the American Type Culture Collection (ATCC), namely, ATCC 50005 (chloroquine resistant) and ATCC 50028 (chloroquine sensitive). The methods of culture and culture materials used in the experiments described herein are known in the art and discussed in Trager W. and Jensen, J., "Human Malaria Parasites in Continuous Culture" Science, 93:673-675 (1976).
Assays for growth inhibition of P. falciparium were performed using the above parasites in standard 96-well test plates. All assays were performed in duplicate. The tests involved the use of a dequalinium chloride salt solution (from the Sigma Company of St. Louis, Mo.--product no. D3768) at concentration levels of 32, 16, 8, 4, 2, 1, and 0 nanograms/ml.
The parasites were permitted to incubate in the test media for 72 hours. At 24 hour intervals, new media and test substances were added, and an aliquot of the incubation mixture was removed for microscopic examination, In addition, the parasites were examined by flow cytometry using the techniques discussed in Makler, M. T., et al., "Thiazone Orange: A New Dye for Plasmodium Species Analysis" Cytometry, 8:568-570 (1987).
The entire experiment was terminated after three days. The data in FIG. 1 clearly illustrates the effectiveness of dequalinium salts against chloroquine-resistant parasites. The "Y" axis in FIG. 1 involves the percentage of erythrocytes in the test media which were infected with viable parasites. The "X" axis involves the concentration of dequalinium chloride used (in nanograms/ml.) At 0 nanograms/ml, parasite growth was extensive, with a % parasite infection of about 17 % after 72 hours. However, at a concentration level of 1.0 nanogram/ml and above, parasite growth was strongly inhibited, and after 72 hours, no viable parasites remained. Similar results were obtained with the chloroquine-sensitive strains of parasite.
The foregoing tests clearly demonstrate the remarkable effectiveness of dequalinium compounds against malaria parasites, including those which are chloroquine resistant/sensitive. Thus, the present invention represents a substantial advance in the art of malaria treatment which is urgently needed throughout the world.
Having herein described a preferred embodiment of the invention, it is anticipated that suitable modifications may be made thereto by those skilled in the art within the scope of the invention. Thus, the invention shall only be construed in accordance with the following claims:
Claims (5)
1. A method for the treatment of malaria in warm blooded animals afflicted with malaria comprising administering a composition comprising a dequalinium salt wherein said dequalinuim salt is selected from the group consisting of an acetate, chloride bromide, iodide, and salicylate salt;
to a warm blooded animal afflicted with malaria at a therapeutically effective level sufficient to kill malaria parasites within said animal; and
allowing said composition to kill said malaria parasites in said animal.
2. The method of claim 1 wherein about 7.0 mg of said dequalinium salt per kg of animal body weight is administered to said animal.
3. The method of claim 1 wherein said composition is administered to said animal using a technique selected from the group consisting of subcutaneous administration, intravenous administration, intraperitoneal administration, and oral administration.
4. The method of claim 1 wherein said warm blooded animal is a human subject.
5. A method for the treatment of malaria in a human subject afflicted with malaria comprising:
administering about 7.0 mg of a dequalinuim salt per kg of body weight to said human subject, and dequolinium salt being selected from the group consisting of an acetiate, chloride, bromide, iodide and saliylatate salt, said dequalinium salt. being administered in an aqueous solution using a technique selected from the group consisting of subcutaneous administration, intravenous administration, intraperitoneal administration, and oral administration; and
allowing said composition to kill said malaria parasites in said human subject.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/418,086 US4946849A (en) | 1989-10-10 | 1989-10-10 | Method for the treatment of malaria |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/418,086 US4946849A (en) | 1989-10-10 | 1989-10-10 | Method for the treatment of malaria |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4946849A true US4946849A (en) | 1990-08-07 |
Family
ID=23656654
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US07/418,086 Expired - Fee Related US4946849A (en) | 1989-10-10 | 1989-10-10 | Method for the treatment of malaria |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US4946849A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992005803A1 (en) * | 1990-10-04 | 1992-04-16 | The Scripps Research Institute | Self-assembling ion pair drugs |
| US5151420A (en) * | 1988-10-19 | 1992-09-29 | Orion Corporation/Orion Pharmaceutica | Substituted pyridazinones |
| US5863716A (en) * | 1994-09-19 | 1999-01-26 | The Leland Stanford Junior University Board Of Trustees | Treatment of plasmodium |
| CN105919959A (en) * | 2016-06-16 | 2016-09-07 | 安徽省逸欣铭医药科技有限公司 | Dequalinium vaginal tablets and preparation method thereof |
| US10787745B2 (en) | 2014-12-05 | 2020-09-29 | Schlumberger Technology Corporation | Corrosion inhibition |
| US10982337B2 (en) | 2015-10-19 | 2021-04-20 | Schlumberger Technology Corporation | Corrosion inhibition |
-
1989
- 1989-10-10 US US07/418,086 patent/US4946849A/en not_active Expired - Fee Related
Non-Patent Citations (25)
| Title |
|---|
| Bleday, R. et al., Arch. Surg., 121:1272 1275 (1986). * |
| Bleday, R. et al., Arch. Surg., 121:1272-1275 (1986). |
| Bodden et al., Biophy. Res. Comm., 135:574 582 (1986). * |
| Bodden et al., Biophy. Res. Comm., 135:574-582 (1986). |
| Bodden, W. L. et al., "Demonstration of Calmodulin (CAM Inhibition by Cytotoxic Antimitochondrial Agents (Meeting Abstract)", Proc. Annu. Meet. Am. Assoc. Cancer Res., 27:280 (1986). |
| Bodden, W. L. et al., Demonstration of Calmodulin (CAM Inhibition by Cytotoxic Antimitochondrial Agents (Meeting Abstract) , Proc. Annu. Meet. Am. Assoc. Cancer Res., 27:280 (1986). * |
| Bullough, D. A. et al., J. Biol. Chem., 264:9155 9163 (1989). * |
| Bullough, D. A. et al., J. Biol. Chem., 264:9155-9163 (1989). |
| Chemical Abstracts 107:223327r (1987). * |
| Chemical Abstracts 109:167179w (1988). * |
| Choi, I. and Mugo, J. L., Mol. Biochem. Parasit., 31:71 78 (1988). * |
| Choi, I. and Mugo, J. L., Mol. Biochem. Parasit., 31:71-78 (1988). |
| Makler, M. T. et al., Cytometry, 8:568 570 (1987). * |
| Makler, M. T. et al., Cytometry, 8:568-570 (1987). |
| Merck Index, 9th Ed., 1976 (compounds 2873 2874 p. 381). * |
| Merck Index, 9th Ed., 1976 (compounds 2873-2874--p. 381). |
| Rotenberg, S. A. et al., Proc.Annu. Meet. Am. Assoc. Cancer Res., 30:a25 (1989). * |
| Scheibel, L., Proc. Nat. Acad. Sci., 84:7310 7314. * |
| Scheibel, L., Proc. Nat. Acad. Sci., 84:7310-7314. |
| Trager, W. and Jensen, J., Science, 193:673 675 (1976). * |
| Trager, W. and Jensen, J., Science, 193:673-675 (1976). |
| Weiss, M. J. et al., Proc. Nat. Acad. Sci., 84:5444 5448 (1987). * |
| Weiss, M. J. et al., Proc. Nat. Acad. Sci., 84:5444-5448 (1987). |
| Wernsdorfer, W. H. et al., chapter 51, "Recent Progress of Malaria Research", Malaria, Principles and Practices of Malariology, vol. 2, Churchill Livingston Co., London (1988). |
| Wernsdorfer, W. H. et al., chapter 51, Recent Progress of Malaria Research , Malaria, Principles and Practices of Malariology, vol. 2, Churchill Livingston Co., London (1988). * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5151420A (en) * | 1988-10-19 | 1992-09-29 | Orion Corporation/Orion Pharmaceutica | Substituted pyridazinones |
| WO1992005803A1 (en) * | 1990-10-04 | 1992-04-16 | The Scripps Research Institute | Self-assembling ion pair drugs |
| US5863716A (en) * | 1994-09-19 | 1999-01-26 | The Leland Stanford Junior University Board Of Trustees | Treatment of plasmodium |
| US10787745B2 (en) | 2014-12-05 | 2020-09-29 | Schlumberger Technology Corporation | Corrosion inhibition |
| US10982337B2 (en) | 2015-10-19 | 2021-04-20 | Schlumberger Technology Corporation | Corrosion inhibition |
| CN105919959A (en) * | 2016-06-16 | 2016-09-07 | 安徽省逸欣铭医药科技有限公司 | Dequalinium vaginal tablets and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| White et al. | Quinidine in falciparum malaria | |
| Wernsdorfer | Epidemiology of drug resistance in malaria | |
| Bryceson et al. | Visceral leishmaniasis unresponsive to antimonial drugs II. Response to high dosage sodium stibogluconate or prolonged treatment with pentamidine | |
| Cook | Prevention and treatment of malaria | |
| Warrell | Cerebral malaria: clinical features, pathophysiology and treatment | |
| EP0362810B1 (en) | Antimalarial compositions using quinidine, artemisinine and its derivatives | |
| Grewal | Pharmacology of 8-aminoquinolines | |
| US6124315A (en) | Method for potentiating primary drugs in treating multidrug resistant disease | |
| Chiari et al. | Potential use of WR6026 as prophylaxis against transfusion-transmitted American trypanosomiasis | |
| Bunnag et al. | Plasmodicidal effect of desferrioxamine B in human vivax or falciparum malaria from Thailand | |
| AU614515B2 (en) | A pharmaceutical combination for the prophylaxis and therapy of malaria | |
| US4946849A (en) | Method for the treatment of malaria | |
| Winstanley et al. | Currently important antimalarial drugs | |
| JPS6256426A (en) | Medicinal composition for treating human malaria | |
| Ibezim et al. | Current trends in malarial chemotherapy | |
| Baum et al. | Successful treatment of cutaneous leishmaniasis with allopurinol after failure of treatment with ketoconazole | |
| Dey et al. | Search for structurally diverse heterocyclic analogs as dual-acting antimalarial and antileishmanial agents: an overview | |
| NZ217431A (en) | Synergistically antimalarial combination preparations comprising an iron(iii) chelating agent and a schizontocide | |
| CA2103707C (en) | Treatment of non-small cell lung carcinoma | |
| Sinou et al. | In vitro and in vivo inhibition of erythrocytic development of malarial parasites by docetaxel | |
| Obaldía | Clinico-pathological observations on the pathogenesis of severe thrombocytopenia and anemia induced by Plasmodium vivax infections during antimalarial drug efficacy trials in Aotus monkeys | |
| Howells et al. | A comparison of the pyrimethamine and cycloguanil sensitivities of the pre-erythrocytic and erythrocytic stages of drug-sensitive and-resistant strains of Plasmodium yoelii | |
| JPWO1995008334A1 (en) | antimalarial drugs | |
| Kain | Antimalarial chemotherapy in the age of drug resistance | |
| Kurup et al. | Chronology of drug development for malaria |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: FLOW INCORPORATED, OREGON Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:MAKLER, MICHAEL T.;REEL/FRAME:005157/0838 Effective date: 19891009 |
|
| CC | Certificate of correction | ||
| CC | Certificate of correction | ||
| REMI | Maintenance fee reminder mailed | ||
| FPAY | Fee payment |
Year of fee payment: 4 |
|
| SULP | Surcharge for late payment | ||
| FPAY | Fee payment |
Year of fee payment: 8 |
|
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
| FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20020807 |